SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    3772, 2929, 18846, 2913, 1735, 1736, 
    3780, 1737, 3769, 1733, 1738, 3782, 
    18844, 1734
  )

Query time 0.00078

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 14,
          "filtered": 100,
          "index_condition": "cscart_products.product_id in (3772,2929,18846,2913,1735,1736,3780,1737,3769,1733,1738,3782,18844,1734)"
        }
      }
    ]
  }
}